WEST HAVEN, Conn. — The microscope at the University of New Haven, set at 10-times magnification, shows a marijuana leaf covered with dozens of tiny bumps. It’s mold, and someone, somewhere could be smoking similarly contaminated pot and not have a clue.

Heather Miller Coyle, a forensic botanist and associate professor at the university, says all sorts of nasty things not visible to the naked eye have been found in marijuana – mold, mildew, insect parts, salmonella and E. coli, to name a few.

That’s why Coyle and her students earlier this year began developing a new process to detect contaminants in marijuana through DNA profiling and analysis. The aim is to be able to identify potentially harmful substances through a testing method that could make the analysis easier and quicker for labs across the country in the developing industry of marijuana quality control testing.

A number of labs around the country are testing marijuana for contaminants using different methods, many of which have been around for decades and used to test other plants, including food crops, for harmful substances.